Power Integrations has announced a breakthrough topology for flyback power supply design. The new TOPSwitchGaN switcher IC family extends the power range of single-ended flyback converters to 440 W, allowing engineers to achieve high efficiency and performance without employing complex resonant or LLC topologies. This makes it ideal for high-end appliances, e-bike chargers, or industrial applications. In addition, we will talk about an industry first: 2200V GaN technology. This positions PowiGaN as the leading technology solution for high-voltage data centers, EVs, renewable energy, and HVDC infrastructure.
Overview
Gallium-nitride (GaN) technology has enabled super-small rapid chargers to delight customers looking to quickly charge their mobile devices. For those applications, the cost penalty of using a wide bandgap semiconductor in place of a high voltage MOSFET was offset by the smaller size of the charger. The size saving was due to the 25-30% reduction in energy lost as heat, which in turn allowed for smaller heatsink elements, thus making the finished power supply physically smaller.
The use of GaN in the TOPSwitchGaN family exploits another facet of the GaN technology: more power. Single ended flyback circuits reach a nominal power limit when the I2R losses of the switch become dominant. Attempting to overcome conduction losses with progressively bigger switches results in unacceptable switching losses. Conventional solutions require the shift to half-bridge circuits with lower forward current supported by resonant switching (i.e. the so-called LLC architecture). GaN changes the relationship between conduction and switching losses, allowing much higher power before a shift to more expensive resonant double-ended circuits.
Finally, we will look at where GaN can be expected to go in terms of operating voltage and explain the unique features that make 1250/1700 and 2200 V switches made possible by the PowiGaN GaN-on-Sapphire and cascode architecture approach for the power switch. We will finish by suggesting the possible routes for GaN going forward and suggest how GaN and SiC based switch-technologies may coexist in the future
Key Takeaways
- Discover how and why GaN can increase flyback power to > 400 W
- Achieve high efficiency across the load range
- Learn why 2200 V GaN is now a reality
- Explore what a cascode brings to reliability
- Discuss the importance of ZVS for high voltage switching
Speaker
Andrew Smith has more than 40 years' experience in power conversion, with a career that started during the transition from SMPS with BJTs to the first MOSFETs. Andrew started work as a power supply design engineer in the UK before transitioning to various roles in power supply and MOSFET design prior to joining Power Integrations in 2004. He has worked on products supporting the consumer, telecom, aerospace, and military power conversion markets. Andrew holds a Bachelor of Engineering Degree (First Class) in Electrical Engineering from Middlesex University in England.